Control Preparation of Sulfated Zirconia by Sol-Gel Process: Impact on Catalytic Performances During n-Hexane Isomerization

Abstract

Sulfated zirconia catalysts were prepared by sol-gel method using CH₃COOH as in situ water source to control hydrolysis of alkoxide, and following two sulfation procedures. The samples were characterized by N₂ adsorption, XRD, chemical analysis, and the activity for isomerization of n-hexane was assessed. It was found that sulfation procedure and the amount of acetic acid added exert a great influence on the catalysts properties. Mixture of sulfuric acid with zirconium propoxide before addition of acetic acid allows the retention of a larger amount of sulfur after calcination and enhances catalytic performances of sulfated zirconia. The use of CH₃COOH reduces the rate of hydrolysis, and improves considerably acidic and catalytic properties.